combining bath exhaust

[mlawrence]

I've got a separate shower and water closet in the bathroom and my plan was to vent these two fans up into a conditioned attic and then combine them with a separate bathroom and vent them all through the side of the house. I know there are couple of companies that make remote fans and stuff for just this situation but why can't I use the regular ceiling mounted fans and just combine them all in the attic? The longest pipe run would be around 12'.

[PEW]

Can be done, have done it with success. However, depending on duct size you may not get the same volume when both are running at the same time vs one at a time.

Have found it works best when both fans are the same size.

[jadnashua]

RUnning the fan in one place could just end up blowing it back into one of the others. You'd need good dampers. One remote fan would be quieter.